The present technology relates to a process for producing sodium titanate and sodium titanate ion exchange media, preferably from nano-crystalline titanium dioxide. The sodium titanate ion exchange media can be subsequently used to remove contaminants such as metals from water in a variety of applications.
Various methods of producing sodium titanates from liquid, solid and semi-solid titanium sources are known. When a solid source has been used, it has required an “exotic” solid sesqui-oxide of titanium as well as autoclave temperatures and pressures.
The removal of metals from water and process solutions is currently achieved through many means including the use organic or inorganic ion exchange as well as adsorbent media. Lead reduction in drinking water is specifically accomplished through the use of weakly acidic acrylic-based cation exchange resins when a large particle (500+ um) can be employed. When a powdered adsorbent/exchanger is employed (<100 um), as in a carbon block filter, this same ion exchange resin is avoided due to its propensity to shrink and swell upon hydration and when changing ionic forms. Inorganic exchangers and adsorbents experience less “size change” under these conditions. These materials include but are not limited to titano-silicate and metal oxide media. Sodium titanates have not traditionally been used in this application.